Tilting mechanism for X-ray examination tadles



TILTING MECHANISM FOR X-RAY EXAMINATION TABLES Filed Dec. 2. 1952 Feb. 8, 1955 H. E. KOER'NER ETI'AL 2 Sheets-Sheet l INVENTORS Harry E. Koerner and John H. Bamz ZM ATTORNEY Feb. 8, 1955 H. E. KOERNER ETAL 2,701,744

TILTING MECHANISM FOR X-RAY EXAMINATION TABLES Filed Dec. '2. 1952 2 Sheets-Sheet 2 WITNESSES: |NVENTQR$ Z Harry E. Koemer and W John H. Bantz TORNEY United States Patent TILTING MECHANISM FOR X-RAY EXAMINATION TABLES Harry E. Koerner and John H. Bantz', Baltimore, Md., assignors to Westinghouse Electricv Corporation, East Pittsburgh, Pa.,. a corporation of Pennsylvania Application December 2, 1952, Serial No. 323,650

3 Claims. (Cl. 31I-6) Our invention relates to X-ray examination tables which. may be tilted relative to the horizontal about a releasable fulcrum at either end as chosen by the operator, and it relates in particular to a safety lock which insures. that. the table cannot be released from the fulcrum chosen while in a. tilted position.

Modern practice in medical X-ray examination. requires a table on which the patient can. recline and. which can be tilted through 90 degrees relative to the horizontal in either direction, so that the patients-head may be higher than his feet when desired, and. also so that, in. what is known as the Trendelenberg position, his feet are above his head. It is also universal practice to. attach the X- ray tube to the under sideof this tiltable table so that its position relative to the patient is not disturbed when the table tilt is altered. An example of such a table is. described in U. S. Patent 2,224,262; to W, H. Haupt,

It is self-evident that in' any such arrangement disastrous results would follow if thepivot on which thetable was resting could be released when. the table was in a tilted position.

Generally, the object of our invention is to. provide an improved pivot locking mechanism for a tiltable. double fulcrum examination table.

More specifically, the object. of our invention is. to provide an improved form of pivot locking mechanism for a tiltable double fulcrum examination table which will positively prevent release of either fulcrum pivot except when the table is in its horizontal position.

Stated another way, the object of our invention is to provide a simplified. pivot locking mechanism for'an examination table which is. tiltable about releasable fulcrums near its respective ends, which locking mechanism shall be foolproof in its operation.

Figure 1 is a schematic side view of the. mechanism for controlling the tilt of a typical X-ray examination table in accordance with our invention when the table is in its horizontal, or untilted, position.

Fig. 2 is a fragmentary view taken parallel to the table axis, and to enlarged scale, of the slot constituting our novel pivot-locking device as it stands when the table is in its untilted position.

Fig. 3 is a similar view taken transverse to the table axis of the Fig. 2. elements.

Fig. 4 is a schematic view' similar to Fig. 1, showing-the mechanism in its condition when the table is tilted through 90 degrees to the so-called vertica position in which the patient is standing erect. 7

Figs. 5 and 6 are respectively views of the same locking-elements as Figs. 2 and 3 when the table has started to tilt toward its vertical position.

Fig. 7 is a schematic view similar to. Fig. Lshowing the mechanism in its condition when the table is tilted through 90 degrees to the so-called Trendelenberg position in which the patients feet are higher than his head.

Figs. 8 and 9 are respectively views of the same locking-elements as Figs. 2 and 3 when the table has started to tilt toward its Trendelenberg position.

Fig. 10 is a schematic side view similar to Fig. l, of an alternative form which the table-locking mechanism may take; and

Fig. 11 is a fragmentary view somewhat similar to Fig. 3 of a slotted portion in Fig. 10.

Referring in detail to the drawings, the X-ray examination table is shown in dotted outline and comprises a base 1 supporting in horizontal position the table top 2 on which the patient undergoing examination lles. The

2,701,744 Patented Feb. 8, 1955 top- 2 is supported by a box-like frame, or chassis. 3, which may be tilted, at the will. of the. operator, about either of two releasable pivots. fixed to. the. chassis 3 at points 4, and 5.. The. base. 1 is hollow and contains. amotor (not shown). and mechanical links 6-,. 7,- bywhich an, upward push; can be exerted at the midpoint. of chassis. 3, thereby tilting the chassis. 3 and, table top- 2 about the one of the two pivot-points. 4, 5 which the operator has selected. The tilt may be made at any angle up to degrees at either end, and. its direction is: dependent, upon which of the. pivots 4 or 5 is engaged by a releasable fulcrum. member such as latch-hook 8- or 9, which respectively turn upon pivots 11 or 12 fixed in base. 1.

The X-ray tube (not shown) is supported within the chassis 3 and, as. is' conventional, is provided with. means by which the operator may move it both crosswise and lengthwise of table: 2 to i-rradiate any desired portion of the patients body.

The latch-hooks 8 and 9 are interconnected by a latchbar 13 pivoted to each. Whenthe latch-bar 13 is moved to the right in Fig 1,, latch-hook 8.- engages pivot 4 and latch-hook. 9 is moved far enough away from. pivot 51 so that the latter may move upward freely past the end of the. hook. Conversely, when. latch-bar 13 is moved to the left, hack. 9 engages pivot 5. preventing it from movmg upward. and causing chassis 3 to.- pivot on 5- if its leftend is raised.

Force to move chassis 3 to a til-ted, position is applied by a reversible electric motor (not shown) whose direction of rotation is under control of. the. operator. This motor 1s geared to turn. a, hull-s rocket icurualled on the base 1 and attached. to the cran arm, 6- which is pivoted to link 7 which, turn, is pivoted to the midpoint of chassis 3.. In the untilted: position of the table 2,, the members 6 and 7 occupy the. position shown in Fig. 1, in which the pivot conne ting memb rs 6 and 7 is. vertically below the axis. on which bull-sprocket 14 turns. Turning bull-sprocket 14 in either direction, therefore, exerts. an upward force. on the pivot connecting link 7 to chassis 3. and tends to tilt table. 2 about the on of pivots 4 and 5 which is engaged by one of the books. 801- 9.

The arrangement for insuring that either latch-hook 8 or latch-hook 9. is moved to and retained in engagement with its associated, pivot 4 or 5, which is an imortant feature of our invention, comprises the latchar 13. and an associated linkage. comprising links, 15 and 16', a. cam 17 and a cam-follower 18- carried by crank-arm. 6. Cam 17 and link 15- turn on. pivots 19 and 21 respectively on, base 1, and link 16 is pivotally connected to each of them asshown. The upper end. of link 15 has slotted engagement with a, pin 22 on latch bar 13.

The contour of the cam 17 is such that when, cranharm' 6 and bull-sprocket 14 are rotated counterclockwise cam 17 turns clockwise causing link 15. to turn clockwise on pivot 2.1 and move latch-bar 13 to the. right (see Fig. 4) to engage latchhook 8 with pivot 4 and completely free pivot 5 from any restraint by latch-hook 9-. The concomitant upward force exerted through link 7 on chassis 3 starts its tilt in a counterclockwise direction about pivot 4.

If, on the other hand, rotation of bull-sprocket 14 had been started in a clockwise direction from that shown in Fig. l, the cam-face of cam 17 is so shaped that link 15 would have turned counterclockwise to move latchhook 9to engage pivot 5 and latch-hook 8 free of pivot 4, thereby permitting link 7 to tilt chassis 3 clockwise about pivot 5, (See Fig. 7.).

Once cam-follower 18. moves beyond the end of the cam face'onf cam 17, bull-sprocket 14 and crank arm 6 can continue to be rotated in the direction they start in until the linkage 6 and 7 .has reached one or the other of the positions shown iii-Figs. 4 and 7, unless the operator stops the motors atsome intermediate point. The locking device now about to be described insures that latchbar 13 and latch-hooks 8 and 9 cannot again be moved until the arrangement has been returned completely to the position shown in Fig. l by the operators action in reversing the motor.

The teeth on the bull-sprocket 14 with which the motorgearing meshes are cut on an annular member such as rim 23, which is provided with a gap or groove 24, shown in enlarged detail in Figs. 2 and 3. This gap 24 is so positioned that it is opposite the latch-bar 13 when the table is in its untilted position, and a blocking-element such as safety-roller 25 is mounted on latch-bar 13 so that it is approximately centered in the gap 24. When bull-sprocket 14 starts to rotate counterclockwise, for example, the resulting displacement of latch-bar 13 toward the right (in Fig. l) by action of cam 17 moves the safetyroller 25 to the right far enough so that when, and only when, latch-hook 8 fully engages pivot 4, roller 25 has just passed the radially-inner end of slot 24. A rotation of bull-sprocket 14 through an angle of about one degree sufiices for such displacement of safety-roller 25.

Further rotation of bull-sprocket 14 can now occur, the face of safety roller 25 sliding along the radially-inward face of annular rim 23, but it is impossible thereafter for latch-bar 13 to be moved to the left in Pig. 4 until the gap 24- is again returned to its Fig. 3 position by corresponding rotation of bull-sprocket 14 to its Fig. 1 position in which the chassis 3 is horizontal. The safety-roller 25 and annular rim 23 thus lock the latch-hook 8 in engagement with pivot 4 as long as the chassis is in a tilted position.

Clockwise rotation of bull-sprocket 14 from its Fig. 1 position of course moves the safety-roller 25 to the left past the radially-outward end of gap 24 when the latch-bar 13 is moved to free pivot 4 from hook 8 and engage hook 9 with pivot 5. On further clockwise rotation of bullsprocket 14, the safety-roller 25 engages the outer periphery of rim 23, thereby locking the latch-bar 1.3 against any movement which would permit disengagement of latching-hook 9 from pivot 5.

The length of the cam-face on cam 17 is made such that the cam-follower 18 does not pass ofi it until the safety roller 25 has moved well beyond the edges of gap 24 and fullv engages one or the other face of rim 23.

The Fig. 10 arrangement differs from that of Fig. l in that the cam 17 and mechanical link 6, cam linkage 15, 16 and 18 is dispensed with, the latch-bar 13 being moved to its various positions by engagement of a safety roller 25 proiecting laterally from it with a curved slot in a rim on bull-sprocket 14. Since the parts numbered 1 through and 7 through 14 on Fig. are the same as those similarly numbered in Fig. 1, they will not again be described.

The curved slot which acts on safety roller to move latch-bar 13 is shown more clearly in Fig. ll where 23 is a portion of the rim of bull-sprocket 14 which is provided with an outwardly projecting plate 31 and an inwardly projecting plate 32. The plates 31, 32 and rim 23 are shaped to form a reversely-curved channel in which the safet roller 25 slides in fitting engagement with both walls. The safety roller 25 stands at the midpoint of this channel when the table is at its horizontal position as shown in Fig. 10. When the bull-sprocket 14 is started in, let us say, a clockwise rotation in Fig. ll, the edge of the slot 33 in rim 23 pushes the roller 25 radially outward along the slot, thus as a glance at Fig. 10 will show. displacing safety roller 25 to the left in that figure and moving latch-hook 9 into engagement with pivot 5. As soon as the inner edge of safety roller 25 reaches the radiallyoutward face of rim 23 the inner edge of plate 31 stops further movement of roller 25 and latch-bar 13. and roller 25 thereafter rides the outer face of rim 23 holding latchhook 9 in engagement with pivot 5 until the bull-sprocket 14 and linkage 6', 7 return the table 2 nearly to its horizontal position, at which time roller 25 reenters slot 33 from its radially-outward end.

If bull-sprocket 14 starts to rotate counterclockwise from the position it assumes when the table 2 is horizontal. the roller 25 is displaced toward the radially-inward end of slot 33, thus displacing roller 25 to the right in Fig. 10, engaging latch-hook 8 with pivot 4. Engagement of roller 25 with the inner face of rim 23 holds the latchhook in that position until reversed rotation of the bullsprocket 14 returns the table 2 to its horizontal position and roller 25 to the mid-point of slot 33 through its radially-inward end.

The operation of the Fig. 10 arrangement is the same as that already described for Fig. 1 except for the actuation of the latch-bar 13 by roller 25 as just described.

The locking arrangements disclosed herein have the great advantages of simplicity, ease of manufacture and maintenance, safety and foolproofness.

Certain subject matter herein disclosed is described and claimed in the application Serial No. 347,683 of Everett W. Vaughn, filed on April 9, 1953.

The foregoing disclosure and the showings made in the drawings are merely illustrative of the principles of this invention, and are not to be interpreted in a limiting sense.

We claim as our invention:

1. In an X-ray examination table, a chassis provided with pivots spaced apart by its mid-section about which it may be tilted alternately to raise either end, a pivoted latch-hook for each pivot, said latch-hook being joined by a link for moving them alternately into engagement with said pivots-to permit said alternate tilting, a drive embodying a wheel for raising the mid-section of said chassis to tilt it about the one of said pivots which is engaged by one of said latch-hooks, an annular rim concentric with said wheel and having a gap which engages a blocking-element on said link when said chassis is in its untilted position and through which said blockingelement moves when said link moves either of said latchhooks into engagement with one of said pivots, said blocking-element engaging a face of said annular rim and preventing movement of said link except when said chassis is in its untilted position.

2. In a tilt table of the type in which mechanism is provided to raise either end of the table, a base relative to which said table tilts, a drive embodying a sprocket for tilting said table, a releasable fulcrum member on said base for each end of said table about which it may tilt alternately so that either of its ends may be raised, a link between said releasable fulcrum members holding one of said fulcrum members released While the other is operatively engaged, an annular rim on said sprocket having a gap which embraces a blocking element on said link when both said fulcrums are released, said blocking element moving out of said gap into engagement with one or another of the curved surfaces on said rim when said link is moved with movement of either said fulcrum to operatively engaged position.

3. In combination with a chassis provided with fulcrummembers spaced apart on opposite sides of its mid-point and having release-means connected to each other by a link insuring that only one said fulcrum-member can act as a fulcrum for said chassis to tilt upon at any one time, mechanism embodying a rotatable annular member for tilting said chassis about said one fulcrum-member, an annulus on said annular member concentric therewith and having a gap, and a safety-element on said link positioned Within said gap when said chassis is in its untilted position and which moves out of said gap into engagement with a curved wall of said annulus when said chassis is in any of its tilted positions.

References Cited in the file of this patent UNITED STATES PATENTS 2,224,262 Haupt Dec. 10, 1940 

